A5055501020- Astrophysics and Cosmic Phenomena
- Neutrino Physics Research
- Dark Matter and Cosmic Phenomena
- Radio Astronomy Observations and Technology
- Particle physics theoretical and experimental studies
- Gamma-ray bursts and supernovae
- Pulsars and Gravitational Waves Research
- Solar and Space Plasma Dynamics
- Scientific Research and Discoveries
- Radio, Podcasts, and Digital Media
- Cryospheric studies and observations
- Arctic and Antarctic ice dynamics
- Ionosphere and magnetosphere dynamics
- Noncommutative and Quantum Gravity Theories
- Atmospheric Ozone and Climate
Georgia Institute of Technology
2019-2024
RWTH Aachen University
2020
University of California, Irvine
2019
This Letter presents the results from pointlike neutrino source searches using ten years of IceCube data collected between April 6, 2008 and July 10, 2018. We evaluate significance an astrophysical signal a looking for excess clustered events with energies typically above ∼1 TeV among background atmospheric muons neutrinos. perform full-sky scan, search within selected catalog, catalog population study, three stacked Galactic searches. The most significant point in northern hemisphere...
We report three searches for high energy neutrino emission from astrophysical objects using data recorded with IceCube between 2011 and 2020. Improvements over previous work include new reconstruction calibration methods. In one search, the positions of 110 a priori selected gamma-ray sources were analyzed individually possible surplus neutrinos atmospheric cosmic background expectations. found an excess $79_{-20}^{+22}$ associated nearby active galaxy NGC 1068 at significance 4.2$\,\sigma$....
We report on the first measurement of astrophysical neutrino flux using particle showers (cascades) in IceCube data from 2010-2015. Assuming standard oscillations, neutrinos this dedicated cascade sample are dominated (∼90%) by electron and tau flavors. The flux, observed sensitive energy range 16 TeV to 2.6 PeV, is consistent with a single power-law model as expected Fermi-type acceleration high particles at sources. find spectral index be γ=2.53±0.07 normalization for each flavor...
Abstract We present a measurement of the high-energy astrophysical muon–neutrino flux with IceCube Neutrino Observatory. The uses high-purity selection 650k neutrino-induced muon tracks from northern celestial hemisphere, corresponding to 9.5 yr experimental data. With respect previous publications, is improved by increased size event sample and extended model testing beyond simple power-law hypotheses. An updated treatment systematic uncertainties atmospheric background fluxes has been...
Gamma-ray bursts (GRBs) have long been considered a possible source of high-energy neutrinos. While no correlations yet detected between neutrinos and GRBs, the recent observation GRB 221009A - brightest observed by Fermi-GBM to date first one be above an energy 10 TeV provides unique opportunity test for hadronic emission. In this paper, we leverage wide range IceCube Neutrino Observatory search from 221009A. We find significant deviation background expectation across event samples ranging...
We report on measurements of the all-particle cosmic ray energy spectrum and composition in PeV to EeV range using three years data from IceCube Neutrino Observatory. The IceTop detector measures induced air showers surface ice, which rays is determined by making additional assumptions about mass composition. A separate measurement performed when are analyzed coincidence with high-energy muon loss information deep in-ice detector. In this measurement, both primary simultaneously...
The IceCube Collaboration has observed a high-energy astrophysical neutrino flux and recently found evidence for emission from the blazar TXS 0506+056. These results open new window into universe. However, source or sources of most neutrinos remains uncertain. Here, search steady point-like is performed using an unbinned likelihood analysis. method searches spatial accumulation muon-neutrino events very high-statistics sample about $497\,000$ recorded by between 2009 2017. median angular...
We present a measurement of atmospheric tau neutrino appearance from oscillations with three years data the DeepCore subarray IceCube Neutrino Observatory. This analysis uses neutrinos full sky reconstructed energies between 5.6 and 56 GeV to search for statistical excess cascadelike events which are signature ${\ensuremath{\nu}}_{\ensuremath{\tau}}$ interactions. For $\mathrm{CC}+\mathrm{NC}$ (CC-only) interactions, we measure normalization be ${0.73}_{\ensuremath{-}0.24}^{+0.30}$...
Continued improvements on existing reconstruction methods are vital to the success of high-energy physics experiments, such as IceCube Neutrino Observatory. In IceCube, further challenges arise detector is situated at geographic South Pole where computational resources limited. However, perform real-time analyses and issue alerts telescopes around world, powerful fast desired. Deep neural networks can be extremely powerful, their usage computationally inexpensive once trained. These...
Abstract We present a catalog of likely astrophysical neutrino track-like events from the IceCube Neutrino Observatory. began reporting neutrinos in 2016, and this system was updated 2019. The presented here includes that were reported real time since 2019, as well identified archival data samples starting 2011. report 275 two selection channels first entries catalog, Event Catalog Alert Tracks, which will see ongoing extensions with additional alerts. Gold Bronze alert respectively provide...
Abstract The IceCube Neutrino Observatory sends realtime neutrino alerts with a high probability of being astrophysical in origin. We present new method to correlate these events and possible candidate sources using 2089 blazars from the Fermi-LAT 4LAC-DR2 catalog 3413 active galactic nuclei (AGNs) Radio Fundamental Catalog. No statistically significant emission was found any searches. result suggests that small fraction, <1%, studied AGNs emit neutrinos pass alert criteria, is compatible...
Using data from the IceCube Neutrino Observatory, we searched for high-energy neutrino emission gravitational-wave events detected by advanced LIGO and Virgo detectors during their third observing run. We did a low-latency follow-up on public candidate released detectors' run an archival search 80 confident reported in GWTC-2.1 GWTC-3 catalogs. An extended was also conducted longer timescales neutron star containing mergers. Follow-up searches optical counterpart of GW190521 were conducted....
We report on a measurement of astrophysical tau neutrinos with 9.7 yr IceCube data. Using convolutional neural networks trained images derived from simulated events, seven candidate ν_{τ} events were found visible energies ranging roughly 20 TeV to 1 PeV and median expected parent energy about 200 TeV. Considering backgrounds atmospheric neutrinos, muons π^{±}/K^{±} decays in air showers, we obtain total estimated background 0.5 dominated by non-ν_{τ} neutrinos. Thus, rule out the absence at...
Abstract We present the results of a search for 10–1000 GeV neutrinos from 2268 gamma-ray bursts (GRBs) over 8 yr IceCube-DeepCore data. This work probes burst physics below photosphere where electromagnetic radiation cannot escape. Neutrinos tens giga electronvolts are predicted in sub-photospheric collision free-streaming neutrons with bulk-jet protons. In first analysis, we searched most significant neutrino-GRB coincidence using six overlapping time windows centered on prompt phase each...
The ordering of the neutrino mass eigenstates is one fundamental open questions in physics. While current-generation oscillation experiments are able to produce moderate indications on this ordering, upcoming next generation aim provide conclusive evidence. In paper we study combined performance two future multi-purpose JUNO and IceCube Upgrade, which employ very distinct complementary routes toward ordering. approach pursued by 20 kt medium-baseline reactor experiment consists a careful...
Abstract Core-collapse supernovae are a promising potential high-energy neutrino source class. We test for correlation between seven years of IceCube data and catalog containing more than 1000 core-collapse types IIn IIP sample stripped-envelope supernovae. search both emission from individual as well combined the whole supernova sample, through stacking analysis. No significant spatial or temporal neutrinos with cataloged was found. All scenarios were tested against background expectation...
Abstract In this work, we present the results of searches for signatures dark matter decay or annihilation into Standard Model particles, and secret neutrino interactions with matter. Neutrinos could be produced in galactic extragalactic Additionally, if an interaction between neutrinos exists then will interact neutrinos. particular induce anisotropy sky is present. We use seven a half years High-Energy Starting Event (HESE) sample data, which measures energy range approximately 60 TeV to...
After the identification of gamma-ray blazar TXS 0506+056 as first compelling IceCube neutrino source candidate, we perform a systematic analysis all high-energy events satisfying realtime trigger criteria. We find one additional known source, GB6 J1040+0617, in spatial coincidence with this sample. The chance probability is 30% after trial correction. For time, present study flux, spectral and optical variability, multi-wavelength behavior J1040+0617 compare it to 0506+056. that shows...
Efficient treatment of systematic uncertainties that depend on a large number nuisance parameters is persistent difficulty in particle physics and astrophysics experiments. Where low-level effects are not amenable to simple parameterization or re-weighting, analyses often rely discrete simulation sets quantify the key analysis observables. Such methods may become computationally untenable for requiring high statistics Monte Carlo with degrees freedom, especially cases where these freedom...
We report constraints on nonstandard neutrino interactions (NSI) from the observation of atmospheric neutrinos with IceCube, limiting all individual coupling strengths a single dataset. Furthermore, IceCube is first experiment to constrain flavor-violating and nonuniversal couplings simultaneously. Hypothetical NSI are generically expected arise due exchange new heavy mediator particle. Neutrinos propagating in matter scatter off fermions forward direction negligible momentum transfer. Hence...
Beginning in 2016, the IceCube Neutrino Observatory has sent out alerts real time containing information of high-energy ($E \gtrsim 100$~TeV) neutrino candidate events with moderate-to-high ($\gtrsim 30$\%) probability astrophysical origin. In this work, we use a recent catalog such alert events, which, addition to announced real-time, includes that were identified retroactively, and covers period 2011-2020. We also search for additional, lower-energy, neutrinos from arrival directions these...
Abstract IceCube alert events are neutrinos with a moderate-to-high probability of having astrophysical origin. In this study, we analyze 11 yr data and investigate 122 selection high-energy tracks detected between 2009 the end 2021. This event (alert + tracks) has an average ≥0.5 being We search for additional continuous transient neutrino emission within events’ error regions. find no evidence significant from any directions. The only locally is associated blazar TXS 0506+056, local...
Abstract During the first three flights of Antarctic Impulsive Transient Antenna (ANITA) experiment, collaboration detected several neutrino candidates. Two these candidate events were consistent with an ultra-high-energy upgoing air shower and compatible a tau interpretation. A third event was in search for Askaryan radiation ice, although it is also background expectation. The inferred emergence angle two tension IceCube ANITA limits on isotropic cosmogenic fluxes. Here we test hypothesis...
We present two searches for IceCube neutrino events coincident with 28 fast radio bursts (FRBs) and one repeating FRB. The first improves upon a previous analysis -- searching spatial temporal correlation of FRBs at energies greater than roughly 50 GeV by increasing the effective area an order magnitude. second is search MeV FRBs. No significant found in either search, therefore, we set upper limits on time-integrated flux emitted range emission timescales less day. These are FRB scale,...